Sintering of the NiFe₂O₄-10NiO/xNi cermet

Abstract

The sintering behavior of NiFe₂O₄-10NiO/xNi cermet which was used as the most prospective inert anode materials for aluminum electrolysis was studied by examining the effects of raw powder particle size, sintering temperature, and the contents of Ni. The results show that fine particle size enables the powder to have high driving force for sintering. High temperature is beneficial to densification, but the ultra-high temperature does harm to the improvement of the density. The samples of NiFe₂O₄-10NiO/5Ni has the highest relative density of 97. 28% when it is sintered at 1 350 °C, but it decreases to 95. 23% when sintered at 1 400 °C. Low addition of Ni has a great help to the sintering of NiFe₂O₄-10NiO matrix. When the samples are sintered at 1 350 °C and the mass fraction of Ni is 5%, the highest relative density is gained, but the density decreases with the further increase of Ni contents. The low density of the sintered samples of NiFe₂O₄-10NiO/17Ni is attributed to the high volume fraction of pores.

Keywords

NiFe₂O₄-10NiO/xNi / sintering / densification / inert anode

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